Automatic gas-operated firearm.



J. C. STURGEON.

AUTOMATIC GAS @FERME-u. FIRE/ARM.

APPLICATION FILED MAR. l`.'19l

Patented Jan. 7,1919.

' ing the locking-lu JOHN C. STURGEON, OF ERIE, PENNSYLVANIA.

AUTOMATIC GAS-OPERATED FIREARM.

Specification of Letters Patent.

Patented Jan. 7, 1919.

Application led March 1`, 1917. Serial No. 151,744.

To all 'whom t may concern:

Be it known that I, JOHN C. STURGEON, a citizen of the United States, residing at Erie, in the county of Erie and State of Pennsylvania, haveV invented certain new and useful Improvements in Automatic Gas- Operated Firearms; and I do hereby declare the following to 'be a full, clear, and exact description of the'invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, forming part of this specification.

This invention relates to automatic gasoperated fire-arms, and has for its objects improvements in the construction and operation of the mechanism thereof.

In accomplishing these objects I provide a frame, to the front end of which I secure a barrel, under the front end of which there is a -cylinder communicating with the bore thereof to receive gas from the discharge of the gun.

In the frame there is a reciprocating breech-bolt having a locking-lug frame secured thereto, in which there is mounted a vertically moving locking-lug having projections on the periphery thereof adapted to engage and 'be disengaged from slots on the inner surface of the frame and be moved backward in longitudinal slots therein.

In the cylinder under the barrel there is a pistonv from which a rod extends backward to the locking-lug and engages an inclined slot therein so that its backward movement, actuated by the force of the gas on the piston, operates to disengage the locking-lug from the frame, and the further backward tra-verse of the piston and rod operates after such disengagement to move the lockin -lug frame backward; and for moving the 0c ing-lug frame forward there is a spiral retracting spring operating against the rear end of the locking-lug frame, and for movinto engagement there is provided a spira spring operating on the `rear end of the rod extending from the piston in the cylinder under the barrel.

For automatically supplying cartridges to the arm, I preferabl secure a cylindrical magazine to the un er side of the gunframe so that the forward end thereof is substantially in line with the rear end of the barrel; this cylindrical magazine being adapted t0 receive a spool of cartridges 'sebe removably attached toE the under side of the gun-frame. For removing cartridges from ythe magazine and presenting them in front of the breech-bolt, I preferably mount a sprocket-wheel in the frame having the teeth on its central part cut away so as to receive the flexible band conveying the cartridges; the teeth of the sprocket wheel engaging thecartridge at each side of the belt so that tlierotation of the sprocket-wheel moves the |belt and cartridges thereon forward at each movement of the sprocketwheel.

For preventing displacement of the belt and cartridges on the sprocket-wheel I preferablyprovide -a spring actuated arm pivoted to the gun-frame so as to extend over l and contact with cartridges on the sprocketwheel; and for operating the sprocketwheel I preferably -provide a longitudinal` cam secured to the front of the locking-lug frame and extending forward under the breech-bolt, which engages and operates dog mechanism which preferably engages ratchet-teeth at lone end of the sprocketwheel so as to maintain the necessary tension of an internal spring in lthe sprocket- Wheel, which spring operates to move the sprocket-wheel forward at the end of each rearward traverse of the breech-bolt. The spring in the sprocket-wheel may, however, be omitted if desired, and the cam-actuated dog mechanism can engage ratchet teeth on the end ofthe sprocket-wheel so that the dog mechanism will act directly on the sprocketwheel -to move it, forward.

These andother` features of the construction and operation of the mechanism of the arm v are hereinafter fully described and illustrated in the accompanying drawings in which Figure 1,V is a side view of a portion of the frame, parts thereof being shown in elevation and parts in section.

Fig. 2, is a transverse section of the same-- on the line A in Fig. 1, looking in the direction of the arrow.

Fig. 3, is a transverse section of the same on the line B inFig. 1, looking in the direction of the arrow.

Fig. 4, is a transverse section of the same on-the line Q in Fig. 1, looking in the direction of the arrow.

Fig. 5, is a view of the sprocket wheel mechanism parti-allyin elevation and partially in section. y

In these drawings 1 indicates a section of the frame .of the arm; 2 a section of barrel, 3 the gas cylinder under the front of the barrel, 4 the piston operating therein, and

' 5 the'rod connecting said piston with the usual mounted on the rear bolt-locln'ng mechanism of the arm: all of these parts being common to gas-actuated automatic guns of the type involved in this invention. The breech-bolt 6 is of the ordinary reciprocatingtype provided with the spring actuated firing-pin shown To this breech-bolt 6 there is secured a locking-frame comprised of sides 7 and 8. Between these sides 7 and 48 there is a bifurcated locln'ng-lugA 9 which embraces the breech-bolt 6 and thepart 5a of the pistonrod 5, passing through and reciprocating in openings in the sides 7 and 8 of the locking-frame.

The part 5L is provided with a transverse stud 10 which engages and operates in inclined slots 11'in the lower ends of the locking-lug 9', whereby the reciprocal movement of the rod 5 operates to move the. lockinglug 9 up and down in the frame'7-.8; the rod 5 being moved-rearwardly by the action of the gas in the cylinder 3, operating on the piston 4; this rearward movement operating to move the locln'ng-lugQ downward and at theI same time compressing the spring 12 part 8 of the lockingframe. rearward movement of The further Athe piston 4 operates tomove the lockinglug frame, the locking-lug mounted therein, and the breech-bolt towwhich the lockinglug frame is secured, to its rearmost position compressing the spiralspringI 13, which, when the pressure on the piston 4 is removed, operates to move the locking-lu frame to its forwardmost position, when t e spring 12 acts to movethe rod 5 and the part 5a 'tliereof, a suflicient distance to raise the lockinglug 9 to its normal accomplished by bringing the lugs 9.a on the locking-lug 9into engagement with the slots 14 in the frame of the arm, locking i the breech-bolt ready for ring.

On the frame 1 opposite thecartridge inlet 15 nof the arm, I mount a sprocket wheel 16 adapted, to be intermittently rotated so as to consecutively bring the spaces between the sprockets thereon inline with the travel of the breech-bolt6, so that at the end of the rearward traverse of the bolt acari-.ridge (not position; this locking is said sprocket-.wheel 'the cartridge in front of the breech-bolt causes it' to c( tact with vand-eject the spent cartridge, which. has been drawn back by the hook 6a onv theend of the breech-bolt during the rearward traverse of the breechbolt through Athe opening 17 in the side of the frame, as illustrated 1n Fig. 2.

The sprocket-wheel- 16 is preferably mounted on a pintle 18 passing through ears 19 and 2O on the frame. The central part 16a of this, .sprocket-wheel is preferably made hexagonal in peripheral contour to receive and supporta belt made of sections hinged together, as more fully hereinafter described.

The central part of the sprocket-wheel 16 is chambered out to receive a spiral spring 21, one end of which engages the sprocket-Wheel and the other the hub 22 of a ratchet pinion 22, so that the spring 21 forms a flexible operative connection between the sprocket-Wheel 16 and the ratchetY pinion 22a as illustrated in Fig. 5; and on the frame there is pivoted a dog 23,which engages the teeth of the ratchet pinion 22":l and prevents rearward movement thereof.

or moving` the ratchet pinion forward there are verticall moving dogs 24 pivoted in a vertically sli ing part 25; this part 25 is provided witha stud 26 which engages a cam-slot 27 ina-part 28 secured to the side 7 of the locking frame, as illustrated in Figs. 1 and 3, under the breech-bolt -6 and travels forward and backward in unison` therewith. This cam-slot 27 operates on the stid 26 during the forward traverse of the breech-bolt to raise the part 25 and the dogs 24 pivoted therein, the teeth of the kratchet pinion 22, and the backward traverse of the bolt and cam moves the part 25 and the dogs 24 downward, thereby winding up the spring 21; the sprocket being meanwhile prevented from turning by the pressure of the bolt between the sprocketsof the sprocket-wheel; but when the bolt which dogs engage has completed its backward traverse and is withdrawn from the sprocket wheel, the power stor di in the spring'operates on the sprocket-wheel 16 to rotate it forward one notch; this distance of rotation of the i sprocket-wheel being governed by the spring dog 29. mounted on the frame, which contacts wlth the incoming cartridges 30-31'011 This operation ls'conse'cutively repeated at each forward and rearward movement. ofthe breech-bolt until the supply of cartridges is exhausted.

For supplying cartridges to the 'sprocketwheel 16 I preferably use a belt made of sections 32 on each of which sections there are as illustrated in Fig. 2.

clips 33-34: and 35-36 adapted to embrace and hold a cartridge thereon, and these sections 32 are hinged together by hinges 32a so that they form a continuous belt or chain, each section of which carries a car- (consecutive removal`of Vthe cartridges by the action of the breech-bolt pushing them out through the clips 33-34 and 35-36 the l empty belt passes downward through a passage 37 and out through an opening 38 at the side of the frame 1.

This method of feeding cartridges from a belt is" not desirable, and I have devised what I believe to be a more desirable one. This I do by providing on the frame 1 of vthe arm a U-shaped extension 39 extending downwardly therefrom, in which extension I secure a cylindrical magazine 40 adapted to receive and support spools 41 upon which the cartridge carrying belt 32-32n can be wound, as illustrated in Figs. 2 and 3; access being had to' this magazine 4 0 for the insertion and -removal of the spools 41 by opening the hinged side 42 of the magazine 40, and when a full spool of cartridges has.

been inserted in the magazine, the end of the belt 32-32a is placed upon the sprocketwheel 16 and the door 42 closed, as illustrated in Fi 2, the cartridges will be'continuously fe to the arm until the spool 41, is exhausted, when ak new spool can be inserted in the magazine as desired.

The operation of the several parts of the mechanism has been so clearly described 'in connection with the description of the parts of the mechanism that further description of their operation is deemed unnecessary.

I have thus shown and described my invention so as to enable others skilled in the art to which the invention appertains to construct and operate the same. I do not, however, confine myself to the exact construction, arrangement and combination of parts thereof, as many modifications can be made therein without departing from the spirit of my invention.

Therefore what I claim as new and desire to secure `by Letters-Patent, is

breech-bolt, and a cam under the breech-bolt engaging and operating said cartridge moving mechanism.

2. In a gun, a gun-frame having cartridge inlet and outlet openings at opposite sides thereof, a breech-bolt mountedv in the frame and reciprocating between the cartridge inlet and outlet openings therein, a cartridge ma azine, adapted to contain a spool of cartri ges removably secured to a flexible band, secured to the underside of the gun-frame, a sprocket-wheel, having the central part of its periphery cut away to receive the cartridgeV carrying bandymounted between the cartridge inlet and outlet openings' in the gun-frame, and a reciprocating cam secured under the breech-bolt and moving in unison ^`therewith for operating said sprocket-wheel.

3. In a gun, a gun-frame, a breech-bolt, a

locking-lug frame secured thereto, a verti.

cally movable locking-lug therein, means for operating said locking-lug, locking-lug frame and breech-bolt, a cartridge magazine secured to the under side of the gun-frame adapted to contain a` spool of cartridges removably secured to a flexible belt, a sprocketwheel over which said belt operates, a motor spring in said sprocket-wheel, a longitudinal cam under the breech-bolt, and dog mechanism engaged by said cam for maintaining the tension of said motor spring.

4. In a gun, a. gun-frame having cartridge inlet and outlet openings in op osite sides thereof, a breech-bolt mounte between said openings, bolt locking mechanism therefor, gas operated mechanism;- for unlocking said bolt-locking mechanism and moving the bolt rearwardly, spring mechanism for moving the bolt forward and locking'it; a cartridge moving sprocket-wheel,

a flexible cartridge-band having cartridges removably secured thereto, cam mechanism under the breech-bolt and reciprocating in unison therewith operating on said sprocketwheel to movethe belt and cartridges thereon-forward.v

5.' In a gun, a gun-frame, a breech-bolt mounted therein, a breech-bolt locking mechanism secured thereto, gas operated mechanism for unlocking Athe breech-bolt and moving it backward, spring mechanism for moving the breechbolt forward and locking it, a cartridge moving sprocketwheel, a cam under the breech-bolt and moving in unison therewith for operating said sprocket-wheel, and a spring operated arm engaging cartridges on said sprocketwheel.

6. In a gun, a gun-frame having cartridge inlet and `outlet openings in opposite sides thereof, a breech-bolt mounted in said gun-frame and reciprocating between said openings, means on said breech-bolt for locking it to the n-frame, means for moving the breech-bolt and its locking mechanism, a sprocket-wheel mounted opposite tov the cartridge inlet in the gunjframe, a cartridge carrying band operatlng. in a depression in the central portion of the sprocket-wheel, reciprocating cam mechanism operating to intermittently rotate said sprocket-Wheel, and means for preventing the backward movement of the sprocketwheel. y y

7. In a gun, a gun-frame, a barrely vsecured to Ithe front end of said frame, a cylinder under the front portion of the barrel communicating Withithe bore thereof, a breech-bolt, locking` mechanism secured thereto for locking the breech-bolt `to the gun-frame, a piston in said cylinder communicating with the bolt-locking mechanism and adapted to unlock it and move it and the breech-bolt rearwardly, spring mechanism engaging the breech-bolt locking mechanism adapted to move it forward and lock it tothe gun-frame, a cartridge -feeding sprocket-wheel opposite the cartridge inlet opening, a spring actuated arm for engaging cartridges on the sprocketwheel, a cam under the breech-bolt vfor operating said sprocket-wheel, and means for -A limiting the movement of the sprocketwheel.

8. In a gun, a gun-frame, a barrel secured to said frame, a reciprocating breech-bolt, a locking-lug frame onY said breechbolt, a vertically movable locking-lug in said locking-lug frame,

adapted to engage'l said notches, a cylinder under the barrel communicating with the front of the breech-bolt, a

notches in the inside of the Y gun-frame, projections on said locking-lug` frame and moving the locking and 'breech-bolt backward, spring mecha-V the gun frame for. moving cartridges in cam 'Xtending from the locking-lug frame forward under the breech-bolt for intermittently operatingv the sprocketwheel, and stop mechanism for limiting the movement of the sprocketwheel.

9. In an automatic gun, a frame, a reciproc-atingv breech-bolt and bolt locking mechanism, a barrel on the front end of the frame, a cylinder under the barrel communicating with the bore thereof, a piston in said cylindencommunicating with the boltlocking mechanism.` and engaging an inclined slot in the locking-lug member thereof and operating to unlock it, and move it backward, a spring on the bolt-locking mechanism compressed by: the first part of the backward movement of said piston, a spring behind the bolt-locking mechanism adapted to be compressed by the backward movement thereof, and move the bolt-lock ing member forward when the pressure on the piston is released, a sprocket-wheel, a flexible cartridge carrying belt operated thereby, a cam under the breech-bolt recipwhereof I affix my signature. 

